Technical data

Safety Integrated Functions
8.7 Commissioning
Function Manual
Function Manual, 06/2012, 6SL3097-4AB10-0BP4
435
8.7.2.5 Setting the sampling times
Terminology
The software functions installed in the system are executed cyclically at different sampling
times.
Safety functions are executed within the monitoring clock cycle (p9300/p9500). The clock
cycle is displayed in r9780/r9880 for the Basic Functions.
Communication on PROFIBUS is handled cyclically by means of the communication clock
cycle.
During the PROFIsafe scan cycle, the PROFIsafe telegrams issued by the master are
evaluated.
Rules for setting the sampling times
● The monitoring clock cycle (p9300/p9500) can be set between 500 μs to 25 ms.
However, the calculation time required for the Extended Functions in the Control Unit
depends on the monitoring clock cycle, that is, shorter clock cycles extend the calculation
time. The availability of a specific monitoring clock cycle therefore depends on calculation
time resources of the Control Unit.
Calculation time resources on the Control Unit are affected primarily by the enabled
Extended Functions and the selected technological functions.
● The monitoring cycle (p9300/p9500) must be an integer multiple of the actual value
update clock cycle (p9311/p9511) or the communication clock cycle (if p9300/p9500 = 0).
● If Extended Safety Functions are being used, p9311/p9511 must be set ≥ 4 * current
controller cycle, however at least ≥ 2 ms.
Overview of important parameters (see SINAMICS S110 List Manual)
● p9300 SI Motion monitoring clock cycle (Power Module)
● p9311 SI Motion clock cycle actual value sensing (Power Module)
● p9500 SI Motion monitoring clock cycle (Control Unit)
● p9511 SI Motion clock cycle actual value sensing (Control Unit)